Improving grassland management is helping a family team increase stocking rate, cut fertiliser use and produce more milk from forage through robots. Ann Hardy reports
Robotic milking, block calving and maximising the use of grazed grass are not natural bedfellows, but Andrew, Marisa and their daughter Kirstie Baird have successfully pulled off this combination on their Lanarkshire farm.
Farming around 200 acres (81hectares) at Auchnotroch Farm near Auchenheath, the family team has long held the ambition of running one cow per acre (2.5 cows/ha) and maximising milk from forage.
Actions taken to reach this goal include a switch to paddock grazing about seven years ago, at the same time as changing to a multi-cut system for making silage.
“This has allowed us to make better utilisation of grass, and also enabled us to increase the milking herd from 170 to 200 cows,” says Miss Baird.
Also taking part in GrassCheckGB – an industry, academic and levy board collaboration designed to help British farmers improve their grassland management - they say the discipline of measuring grass leads to better decisions over reseeding and grass allocation.
This has also helped the Bairds grow 11-12 tonnes of dry matter (DM) per hectare (4.45-4.85t DM/acre), compared with around 9.5 t DM/ha (3.8t DM/acre) before they took part in the project. This is used to feed their mixed-breed herd giving 8,000 litres at 4.3 per cent fat and 3.3 per cent protein, of which 4,000 litres comes from forage.
It was only in January 2020 that robotic milkers were added to the mix, with four units required for the autumn block-calving herd.
Mr Baird says: “One of the hardest things at the outset was deciding on the size of paddocks to ensure the cows would move on at the correct time to achieve the target of three milkings a day.
“We were told we may have 200 cows waiting for the shedding gate to change towards the fresh paddock.”
Within two weeks of starting to graze, the cattle had adapted to the new system.
Miss Baird says: “We had to fetch 30 or 40 cows to start with, but after two weeks there were only around half a dozen to bring in. Now, by mid-morning, we are not fetching many and often they have all made their way through in groups of two or three.”
With a so-called AB system in place, there are two tracks running into and out of the sheds. These go to either the A or B grazing block which are alternated for grazing, with a new paddock of fresh grass offered each time. Within each block, 4-acre (1.6ha) paddocks are enclosed by permanent fencing, and each is then temporarily sub-divided.
“We find that paddocks of 1-1.5 acres are working well and the herd moves through the three of them every 24 hours,” she says.
The whole grazing platform of 80 acres (32ha) comprises the land on the steading side of the farm. The remainder is cut off by a road, and only used for silage and grazing dry cows, while youngstock are reared away from the farm.
Plate metering has begun this season across the grazing platform with covers averaging 1,700kg dry matter/hectare on March 6.
The goal for pre-grazing covers is 3,000kg DM/ha, which will be grazed down as hard as practicable to maximise tillering and increase the density of the sward. However, a buffer feed of silage is offered for the first three weeks after turnout to help the transition to the new ration.
After turnout, the herd’s concentrate use will drop to as little as 3kg, fed through the robots each day.
Mr Baird says: “After calving, concentrate use will increase with production and in winter can reach 9.5kg/day for cows giving above 55 litres.”
As the season progresses, any surplus grazing may be shut off for silage, but with the farm now stocked to capacity, it is more likely to all come from the fields over the road.
Mr Baird says: “We will cut every five or six weeks, from early May through to mid-September.
“We are looking for an ME of 12MJ/kg DM, which generally we achieve. However, the hardest thing is finding a window of weather to dry the crop, especially for fourth cut.”
Cows are dried off in late summer and housed as they calve, from September. Late autumn growth then produces slightly higher covers of around 1,800kg DM/ha to carry over the winter.
The process of measuring has had the further bonus of identifying paddocks which are not performing.
“Last year, we reseeded 28 acres with a hybrid ryegrass sward which we hoped would compete with an annual meadowgrass problem, and we have certainly seen it bounce back,” says Miss Baird.
Measuring the sward has also identified the benefits of applying slurry with a trailing shoe.
Mr Baird says: “We found a difference in growth of 1 tonne DM per hectare, between this and a splash plate, so we are now using a trailing shoe for everything."
Applying slurry with 20 per cent digestate from a local anaerobic digester, this is boosting nitrogen, potassium and phosphorus, and also helping to cut artificial fertilizer.
“This year we will put on 25kg of nitrogen per hectare between every grazing,” says Andrew. “With the addition of that on the silage ground, this gives us an annual usage of around 173kg of bagged nitrogen per hectare.”